Mostly get drag and drop working

src/lib/util/upload.ts

@@ -3,4 +3,42 @@ export async function requestPersistentStorage() {
     const isPersisted = await navigator.storage.persist();
     console.log(`Persisted storage granted: ${isPersisted}`);
   }
+}
+
+export function formatBytes(bytes: number, decimals = 2) {
+  if (bytes === 0) return '0 B';
+
+  const k = 1024;
+  const dm = decimals < 0 ? 0 : decimals;
+  const sizes = ['B', 'KB', 'MB', 'GB', 'TB', 'PB', 'EB', 'ZB', 'YB'];
+
+  const i = Math.floor(Math.log(bytes) / Math.log(k));
+
+  return `${parseFloat((bytes / k ** i).toFixed(dm))} ${sizes[i]}`;
+}
+
+async function getFile(fileEntry: FileSystemFileEntry) {
+  try {
+    return new Promise<File>((resolve, reject) => fileEntry.file(resolve, reject));
+  } catch (err) {
+    console.log(err);
+  }
+}
+
+export async function scanFiles(item: FileSystemEntry, files: Promise<File | undefined>[]) {
+  if (item.isDirectory) {
+    const directoryReader = (item as FileSystemDirectoryEntry).createReader();
+    await new Promise<void>((resolve) => {
+      directoryReader.readEntries((entries) => {
+        entries.forEach((entry) => {
+          if (entry.isFile) {
+            files.push(getFile(entry as FileSystemFileEntry))
+            resolve()
+          }
+          scanFiles(entry, files);
+        });
+      });
+    });
+  }
+
 }